Elektrik Elektronik Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/411
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Article Citation - WoS: 6Citation - Scopus: 8Squeezed State Generation Using Cryogenic Inp Hemt Nonlinearity(Iop Publishing Ltd, 2023) Salmanogli, AhmadThis study focuses on generating and manipulating squeezed states with two external oscillators coupled by an InP HEMT operating at cryogenic temperatures. First, the small-signal nonlinear model of the transistor at high frequency at 5 K is analyzed using quantum theory, and the related Lagrangian is theoretically derived. Subsequently, the total quantum Hamiltonian of the system is derived using Legendre transformation. The Hamiltonian of the system includes linear and nonlinear terms by which the effects on the time evolution of the states are studied. The main result shows that the squeezed state can be generated owing to the transistor's nonlinearity; more importantly, it can be manipulated by some specific terms introduced in the nonlinear Hamiltonian. In fact, the nonlinearity of the transistors induces some effects, such as capacitance, inductance, and second-order transconductance, by which the properties of the external oscillators are changed. These changes may lead to squeezing or manipulating the parameters related to squeezing in the oscillators. In addition, it is theoretically derived that the circuit can generate two-mode squeezing. Finally, second-order correlation (photon counting statistics) is studied, and the results demonstrate that the designed circuit exhibits antibunching, where the quadrature operator shows squeezing behavior.Article Citation - WoS: 1Citation - Scopus: 2Entangled State Engineering in the 4-Coupled Qubits System(Elsevier, 2023) Salmanogli, AhmadThis article studies the behavior of the avoided level crossing in the 4-coupled qubit to each other and mainly focuses on how to engineer it. This phenomenon occurs due to the two transitions out of the ground state in a two-coupled qubit, contributing to the entangled states. This essential and unique behavior can be engineered in a quantum circuit. For this reason, a quantum circuit containing 4 qubits is designed, and its quantum Hamiltonian and dynamic equation of the motion are theoretically derived. Analysis of the entanglement between each coupled qubit using the entanglement metric reveals that the strength of the qubit-qubit coupling factor and the qubit's non-linearity play an essential role in engineering the photonic mode entanglement. The results show that the avoided level crossing appears in the photonic mode entanglement. In other words, two or more transitions from the ground state to the multiple excited states for each bias current. However, the interesting point is that the avoided level crossing just occurs for the qubits connected capacitively to the driven field (the first qubit in this work), not for all.& COPY; 2023 Elsevier B.V. All rights reserved.Article Citation - WoS: 1Citation - Scopus: 1Enhancing Quantum Correlation at Zero-If Band by Confining the Thermally Excited Photons: Inp Hemt Circuitry Effect(Springer, 2023) Salmanogli, AhmadThe microwave quantum correlation as a crucial issue in quantum technology is analyzed and studied. An open quantum system operating at 4.2 K is designed in which InP HEMT as the nonlinear component couples two external oscillators. The quantum theory is applied to analyze the system completely. The Lindblad Master equation is used to analyze the time evolution of the expanded closed system that covers the environmental effects. In the following, the state of the system defined is determined in terms of the ensemble average state using the density matrix; then, the ensemble average of the different operators is calculated. Accordingly, the covariance matrix of the quantum system is derived, and the quantum discord as a key quantity to determine the quantum correlation is calculated. As an interesting point, the results show that InP HEMT mixes two coupling oscillator modes so that the quantum correlation is created at different frequency productions, especially the zero-IF band. Nonetheless, the main point is that one can strongly manipulate the quantum correlation in the zero-IF using circuitry engineering. It is established by increasing the operational frequencies in the quantum system leading to dramatically limiting the thermal noise since the zero-IF band remains unchanged.Article Entangled Two-Photon Interference(Elsevier Gmbh, 2019) Salmanogli, AhmadThis article proposes a theoretical solution to one of the original problems of the double-slit experiment, which expresses that it is impossible to identify the photon's path without disturbing it We contend that using the entangled two-photon (signal and idler photons) and inserting a double-slit into the beam of signal (idler) photon, it is possible to distinguish the path of signal (idler) photon, just by the detection of the idler (signal) photon. Basically, the signal and idler photons are highly correlated to each other due to the momentum conservation. Indeed, the photon-photon correlation originates the nonlocal interference effect, so using this effect, lets us know about which path the photon goes through, with its conjugate photon's position detection rather than its detection.Article Citation - WoS: 10Citation - Scopus: 10Modification of a Plasmonic Nanoparticle Lifetime by Coupled Quantum Dots(Amer Physical Soc, 2019) Salmanogli, AhmadIn this study, the interaction between a plasmonic nanoparticle and coupled quantum dots is investigated to identify how the coupled particles can manipulate the plasmonic nanoparticle decay rate. This subject is very important, because most applications of the plasmonic system are restricted due to the nanoparticle decay rate and the related losses. Therefore, in the present work, we try to find out how and by which method the plasmonic nanoparticle decay rate can be manipulated. For this purpose, a plasmonic system containing a nanoparticle coupled to some small quantum dots is designed. The system dynamics of motions are analyzed with Heisenberg-Langevin equations. These equations are analyzed to study the effect of the plasmonic nanoparticles on the quantum dots' decay rate. In the following, as an interesting point, the quantum dot coupling influence on the nanoparticle's decay rate is theoretically analyzed in the transient and steady-state conditions. Additionally, a theoretical formula is derived by which one can explicitly find the dependency of the modified decay rate of the plasmonic nanoparticle on the number of the coupled quantum dots and the coupling strength. The simulation results show that it is possible to effectively control the nanoparticles' decay rate with regard to the application for which they are utilized.